package com.kx.kxblog.util;

import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;
import org.springframework.beans.BeansException;

import java.util.HashSet;
import java.util.Set;

public class BeanUtils {
    public static String[] getNullPropertyNames(Object source) {
        final BeanWrapper src = new BeanWrapperImpl(source);
        java.beans.PropertyDescriptor[] pds = src.getPropertyDescriptors();

        Set<String> emptyNames = new HashSet<>();
        for(java.beans.PropertyDescriptor pd : pds) {
            Object srcValue = src.getPropertyValue(pd.getName());
            if (srcValue == null) emptyNames.add(pd.getName());
        }
        String[] result = new String[emptyNames.size()];
        return emptyNames.toArray(result);
    }
    public static <T> T copyProperties(Object source, T target) throws BeansException {
        org.springframework.beans.BeanUtils.copyProperties(source, target);
        return target;
    }

    public static <T> T copyPropertiesIgnoreNull(Object source, T target) throws BeansException {
        org.springframework.beans.BeanUtils.copyProperties(source, target, getNullPropertyNames(source));
        return target;
    }

}
